Excessive Tool Permissions

Category: Privilege & Access Control
Severity: High
MITRE ATT&CK Mapping: T1134 (Access Token Manipulation)

Description

Tools granted overly broad permissions that exceed their functional requirements, creating opportunities for privilege abuse and unauthorized access to system resources.

Technical Details

Attack Vector

  • Over-privileged tool configurations
  • Excessive permission grants
  • Broad access policies
  • Unrestricted tool capabilities

Common Techniques

  • Tool permission abuse
  • Excessive privilege exploitation
  • Broad access exploitation
  • Permission escalation through tools

Impact

  • Unauthorized Access: Tools accessing resources beyond their scope
  • Data Exposure: Excessive permissions leading to data access
  • System Compromise: Tools with system-level permissions
  • Lateral Movement: Using over-privileged tools for further attacks

Detection Methods

Permission Auditing

  • Audit tool permissions
  • Monitor permission usage
  • Detect excessive access
  • Track privilege escalation

Tool Monitoring

  • Monitor tool activities
  • Track resource access
  • Detect permission abuse
  • Analyze tool behavior

Mitigation Strategies

Permission Management

  • Implement least privilege principles
  • Regular permission audits
  • Restrict tool capabilities
  • Monitor permission usage

Tool Security

  • Limit tool permissions
  • Implement access controls
  • Deploy monitoring systems
  • Regular security reviews

Real-World Examples

Example 1: File System Tool with Excessive Permissions

# Over-privileged file tool
class FileReaderTool:
    def __init__(self):
        # Excessive permissions - full filesystem access
        self.permissions = ["read", "write", "execute", "delete"]
        self.allowed_paths = ["/"]  # Root access
    
    def read_file(self, path):
        # Should be restricted to specific directories
        if self.has_permission("read"):
            return open(path, 'r').read()
        
        # Attacker reads sensitive files
        # path = "/etc/passwd"

Example 2: Network Tool with Broad Access

# Over-privileged network tool
class NetworkTool:
    def __init__(self):
        # Excessive network permissions
        self.allowed_protocols = ["HTTP", "HTTPS", "FTP", "SSH", "TELNET"]
        self.allowed_ports = range(1, 65536)  # All ports
        self.allowed_hosts = ["*"]  # All hosts
    
    def connect(self, host, port, protocol):
        # Should be restricted to specific services
        return establish_connection(host, port, protocol)
        
        # Attacker connects to internal services
        # host = "internal-database", port = 3306

Example 3: System Tool with Admin Access

# Over-privileged system tool
class SystemTool:
    def __init__(self):
        # Excessive system permissions
        self.permissions = [
            "process_management",
            "user_management", 
            "system_configuration",
            "service_control"
        ]
    
    def execute_command(self, command):
        # Should be restricted to specific commands
        if "system_configuration" in self.permissions:
            return os.system(command)
        
        # Attacker executes arbitrary system commands
        # command = "adduser attacker sudo"

References & Sources

  • Red Hat - “Model Context Protocol (MCP): Understanding security risks and controls”
  • Cisco - “AI Model Context Protocol (MCP) and Security”

Excessive tool permissions create significant security risks by providing attackers with overly broad access to system resources and capabilities.